Guys, anyone pls help me..

Which equation matches the graph shown ?

International calls require the use of a country code. many country codes a 3-digit numbers. country codes do not begin with a 0 or 1. there are no restrictions on the second and third digits. how many different 3-digit country codes are possible?

What is the value of x in the equation (2)3) (x+6)= -18 a. -36 b. -33 c. -24 d. -18